  * {
    margin: 0;
    padding: 0;
  }

  html,
  body {
    width: 100%;
    height: 100%;
    font-size: 20px;
    font-family: '楷体';
  }

  .main {
    width: 230px;
    height: 150px;
    border: 1px solid deepskyblue;
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    padding: 20px;
  }

  #country,
  #city {
    width: 100px;
    height: 30px;
    text-align: center;
    line-height: 30px;
    margin-right: 10px;
    cursor: pointer;
    color: rgba(0, 0, 0, .8);
  }